Blue and ultraviolet cathodoluminescence from Mn-doped epitaxial ZnO thin films

Abstract

Combinatorial laser molecular-beam epitaxy method was employed to fabricate epitaxial Zn1−xMnxO thin films in a high throughput fashion. Local structures around Mn were investigated for these c-axis-oriented epitaxial films by fluorescence x-ray absorption fine structure measurements. It was shown that Mn substitutionally replaces Zn in Zn1−xMnxO (x<0.22) films. Well-structured blue and ultraviolet cathodoluminescence peaks corresponding to the intra-d-shell transitions of Mn2+ were observed, especially for smaller x. The luminescence is quenched rapidly as x is increased. By comparing the relative absorption strength per mole Mn2+ with the statistical probability of isolated Mn2+, it was concluded that the quick decrement of isolated Mn2+ with increasing x is responsible for the severe suppression of the blue and ultraviolet luminescence.

Synthesis of Colloidal Mn2+: ZnO Quantum Dots and High‐Tc Ferromagnetic Nanocrystalline Thin Films.

“…All data were corrected for the diamagnetism of the substrate and sample holder. Figure 1a shows electronic absorption spectra of a 0.10 M DMSO solution of 2% 17,22,37,38 The solid line in Figure 1a shows the spectrum collected after 1.65 equiv of base were added. Base addition beyond ca.…”

High-temperature ferromagnetism in pulsed-laser deposited epitaxial (Zn,Mn)O thin films: Effects of substrate temperature

“…It was argued 15 that Mn-O-Mn clusters are favorable even at relatively lower doping level of Mn. Although Mn 2+ ions can substitute Zn 2+ sites homogeneously in the dilute limit, 10 the isolated state of Mn 2+ is destroyed due to substitutional occupation of the nearest Zn 2+ sites by other Mn 2+ ions for increasing concentration of Mn.…”

Influence of Mn doping on ZnO defect-related emission

“…This effect was accounted for by different sites of Mn ions in the host lattice [8] as well as their interaction with Zn i [2,5,13] and V O [1][2][3][4][5]. The possibility of Mn cluster formation also should be taken into account [6,27]. To elucidate the influence of native defects on Mn-related emission in ZnO:Mn ceramics further investigations are planned.…”